A communication system that relays a wireless ad-hoc network to another network via a gateway apparatus is known. As a technology relating to such communication system, a wireless system is known, for example, which comprises a group of wireless terminals connected to a network, a first collector that communicates with the wireless terminals in a prescribed radio frequency band and functions as relaying means to a center, and a second collector that communicate with the wireless terminals in a radio frequency band different from the aforementioned radio frequency band and functions as relaying means to the center. In this system, the wireless terminals communicating with the first collector and the wireless terminals communicating with the second collector carry out, beforehand, participation into a network where a different radio frequency band is used for communication with each other in order to prepare against failure in the first or the second collector.
As another related technology, a communication method is known which includes a first retrieval process for retrieving a counter communication apparatus on a predetermined communication channel, a second retrieval process for retrieving a counter communication apparatus on all the communicable communication channels, and a retrieval control process for using the first retrieval process and the second retrieval process to retrieve a counter communication apparatus.
Also, a node is known which includes a radio interface for transmitting and receiving data through radio communication, a channel information acquisition section for acquiring information about peripheral radio interfaces as channel information by means of the radio interface, and a communication connection control section which, when a radio interface of the same system permitting configuration of a network with the radio interface is detected from among the acquired channel information, changes the configuration of the radio interface and connects the radio interface with the radio interface of the same system. The node determines whether or not the radio interface is to be connected taking into account the reception signal intensity of the radio interface.
Also, a radio communication network system is known which includes a plurality of sensor nodes, a base station to which the sensor nodes are each connected through or not through a repeater, and radio communication means used for communication carried out within a network including the sensor nodes, repeaters, and the base station. The radio communication means include a plurality of selectable carrier frequency channels, and include channel determination means for determining a carrier frequency channel suitable for communication within the communication network based on information on a connection path between a sensor node and the base station.
Also, a wireless network system is known which a plurality of base stations and wireless terminals is configured. A wireless terminal acting as a base station or a master station transmits communication control information for controlling a communication method for each slave station. A communication control part in each wireless terminal performs communication with its own master station and slave station by a communication method following the communication control information received from the master station, and at the same time, a communication quality measurement part measures the communication quality of a communication route. The base station evaluates the communication quality of each communication route based on the communication qualities collected from a communication quality tabulation part in each wireless terminal to select an optimum communication route to be used for each wireless terminal.
Related art is disclosed in Japanese Laid-open Patent Publications No. 2010-187316, No. 2010-93448, No. 2009-206999, No. 2009-200583, and No. 2010-35068.